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In the natural sciences, researchers use a variety of techniques that rely on extensive man-hours and can therefore be difficult to scale. This obviously limits questions that concern large spatial scales or that involve large numbers of animals. Here, we describe the design and deployment of a wireless sensor network that delivers high resolution sensor data while monitoring seabirds on a UK National Nature Reserve. We describe some of the problems encountered and the solutions we have used. In general, the network has successfully demonstrated its utility in a real world scenario and will be extended and enhanced for the coming field season. Copyright 2008 ACM.

Computational Scientists are both creators and end-users of scientific models. Different aspects to their work target different audiences and generally require different development approaches. The research of computational scientists typically involves the development of new computational models and methods often exposed as services. Complex multi-component models, usually bringing together previously developed and new services into a larger dynamical model, are now frequently developed. The communication of scientific models and their predictions is now a major area of science, with policy makers increasingly turning to scientists for predictions of complex dynamical systems. Scientific model development is also often done collaboratively, with different scientific teams working on components of the larger model, becoming analogous to professional software development. It is therefore not surprising that the majority of scientists consider developing scientific software as important for their own research. Despite the need for software to help conduct and communicate scientific research, computational scientists are generally "end-user programmers" with entirely different goals to Software Engineers when creating and composing software. Here we report outcomes of an experimental collaboration between Software Engineers and Computational Scientists to create a new development environment to encompass diverse end user groups.

Over the last years, the need to interconnect businesses has significantly affected the Web. The Web has moved constantly from a static source of documents to a dynamic platform for distributed applications. The communication infrastructure of the Web links together applications, e.g. by exposing functionality through Web services in different architectural styles. The current strife between SOA and REST leads one to the issue which approach to choose. Supported by a formal model, we show an integrative way to incorporate service orientation and resource orientation in federated systems as a foundation for future agreements rather than a separation of the approaches.

During the last years, the asset costs for storage have been decreasing continuously. Coincidentally, the demand to create and publish data in the Web has grown in an unprecedented manner. Within the Web 2.0, the user became an active part by creating, publishing, changing and annotating data and its related metadata in a wide variety of new kinds of applications. Many data management but also architectural decisions for such applications are driven by distribution and semantic aspects. In this paper, we present how the WebComposition Data Grid Service (WebComposition/DGS) emerges new kinds of data-centric applications as a REST-architectural style component within the context of Web 2.0 but also satisfies requirements within traditional SOA-based business scenarios.

Modern software solutions for distributed applications show a strong need for fast and flexible integration of heterogeneous service technologies, as well as for the orchestration of traditional service-based business scenarios (e.g. SOAP or RPC) and REST-driven approaches. The fulfilment of these requirements in existing enterprise platforms is typically accomplished with parallel working components based on different technologies and APIs, resulting in architectural overhead and increased complexity. The WebComposition/DGS (Data Grid Service) aims at solving this issue with the help of a central service layer which specifies a common plug-in framework used to adapt concrete service protocols and which offers an easy-to-use interface for deploying new logic and services. This approach reduces development effort and overall costs thanks to its coherent and integrated DGS-compatible service architecture with automated support for several protocols.

Today's Web applications and their respective business processes reside under the control of different organizations. Establishing federations between these organizations, i.e. bringing these business processes together by transcending organizational and security borders, raises a new class of security questions concerning the management of trust relationships between the autonomous bodies that wish to work together. Based on the Webcomposition architecture model we provide a modeling approach for federated Web applications. In this paper we present a methodology for formalizing these models using the ambient calculus for use in further computation. Based on the results we help the users to identify and detect security related aspects in Web-based federations.

The need to create, store, maintain, and share data as being part of Web 2.0 labelled solutions requires the application of different skills and tools sets. The growing complexity of these new kinds of applications leads to cost and time-intensive development life-cycle because many data design and management decisions are directly influenced by distribution and semantic aspects. In this paper we propose the Web composition data grid service (Web Composition/DGS) as a supporting service to address these problems. The service acts as a highly integrative core component for data-centric applications, taking traditional SOA-based business scenarios as well as REST-architectural style applications in the Web 2.0 context into account.

Comparing context of different entities is not easy at all. Since context depends on the situation of a particular entity it can be understood in different ways by various entities. In this paper we introduce an approach to consider all entities as environment in which the formal interpretation of all available context and its changes can be quantified and used to find optimal decisions within such an environment-aware system.

Locating physical devices and accessing their functionality in pervasive environments is strongly restricted by their locality. Since there are more and more devices available, waiting to serve users, a simple way is required to access, connect, and most important to locate them in the real world. In this paper we propose an approach to connect and access arbitrary devices by federating them related to their geographical location. This approach allows us to create context-aware federations of devices - the Internet of things

In this paper, we present a high-level graphical language to develop pervasive applications based on a unique interface design. The language supports a wide range of programming constructs. Its graphical notation is based on the LCARS design, which is appealing to different target groups, based on their specific interests and requirements. We show that users can easily create pervasive applications using an LCARS-based user interface. The first step is to describe the technical context in which the application will execute. Based on this technical context, the UI offers a context-specific set of visual primitives. By composing these visual primitives on the screen, the user can specify the behavior of the application.

Electronic devices have been used for the support of everyday tasks in domestic and professional environments for some time now. Currently, there is a tendency towards a combined application of individual gadgets that are connected within locally confined environments via a diversity of protocols and technologies like UPnP, WLAN and Bluetooth. As one step further in this direction, there is the vision of devices that are globally and uniformly connected through the WWW, extending the Mobile Web to a Ubiquitous Web. Hence, this allows for scenarios where actions on one device can trigger events on an arbitrary other device, and where third-party Web services from anywhere in the world are involved. Ultimately, this results in federations of devices and Web services belonging to different households, companies, suppliers and service providers, forming new kinds of Web applications that integrate devices as an additional dimension. To fulfill this vision, solutions are required that are able to abstract from the different device implementations and bridge the gap between the device and the Web. In this paper, we present the Federated Device Assembly (FDX) approach that offers an integrated management platform for wrapping and as such connecting arbitrary devices to enable new forms of Web applications along with the means to model such federations. Furthermore, we demonstrate how the required infrastructure systems can be realized by introducing a reference architecture and a generic Web service interface.